Dual In Situ

Representative histological plates from the caudate-putamen of rats illustrating cells double-labeled for c-fos mRNA and preproenkephalin mRNA in animals given either 5 or 10 mg/kg of amphetamine in a novel environment. Top. Darkfield images in which cells positive for c-fos mRNA are identified by clusters of silver grains. Bottom. Overlay of darkfield and brightfield images. Cells positive for preproenkephalin mRNA are identified with purple precipitate and cells positive for c-fos mRNA are identified by silver grains. Arrows pointing down indicate cells positive for c-fos but not preproenkephalin mRNA. Arrows pointing up indicate cells labeled with preproenkephalin mRNA but not c-fos mRNA. Arrows pointing to the right indicate double-labeled cells (c-fos/ENK+).
from Uslaner et al., in press.